1. School of Computer Science and Technology; Tianjin Key Laboratory of Cognitive Computing and Application, Tianjin University; Tianjin 300350 People's Republic of China
2. State Key Laboratory of Intelligent Technology and Systems; National Laboratory for Information Science and Technology, Tsinghua University; Beijing 100084 People's Republic of China
3. Medical Imaging Research Institute, Binzhou Medical University; Yantai Shandong 264003 People's Republic of China
4. Department of Radiology; Yantai Affiliated Hospital of Binzhou Medical University; Yantai Shandong 264003 People's Republic of China